A sea of Cowboy blue and white at Candlestick

— As Dallas kicker Dan Bailey’s winning 19-yard field goal went through the uprights, a huge roar of approval came from the Candlestick crowd. For a second, it sounded as if he had missed, giving the home team another chance.

But the applause came from a contingent of Dallas fans that almost surpassed the Red Sox partisans who routinely seize control of the Oakland Coliseum, rivaling the presence of A’s supporters. The Cowboys fans routinely made noise on 49ers‘ possessions, chanting “Defense.”

“That was amazing. I don’t know if I’ve ever been involved in a game like that,” said Dallas tight end Jason Witten. “They helped the players, helped the mind-set.”

Quarterback Tony Romo made an even stronger statement. “That was possibly the difference,” he said. “They were loud.”

Safety Donte Whitner, in his first year with the 49ers, didn’t expect to see so many blue and white jerseys.

“I was very surprised,” he said. “They had their own chants. It was almost like a split house.”

He ascribed the large number of Dallas fans to the intensity of the long rivalry between the Cowboys and 49ers, but when these two teams ruled the NFL, 49ers fans would have filled most of the house. As the 49ers have declined, more tickets have become available to opposing fan bases. The Steelers have long drawn a big following here, and a certain number of cheeseheads always find a way to watch the Packers here.

But as Witten said, this game was different. The ‘Stick had practically become a Cowboys’ comfort zone.